sqlcipher/src/delete.c at multi-lib · securitykernel/sqlcipher · GitHub

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** 2001 September 15

** The author disclaims copyright to this source code. In place of

** a legal notice, here is a blessing:

** May you do good and not evil.

** May you find forgiveness for yourself and forgive others.

** May you share freely, never taking more than you give.

*************************************************************************

** This file contains C code routines that are called by the parser

** in order to generate code for DELETE FROM statements.

#include "sqliteInt.h"

** While a SrcList can in general represent multiple tables and subqueries

** (as in the FROM clause of a SELECT statement) in this case it contains

** the name of a single table, as one might find in an INSERT, DELETE,

** or UPDATE statement. Look up that table in the symbol table and

** return a pointer. Set an error message and return NULL if the table

** name is not found or if any other error occurs.

** The following fields are initialized appropriate in pSrc:

** pSrc->a[0].pTab Pointer to the Table object

** pSrc->a[0].pIndex Pointer to the INDEXED BY index, if there is one

Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){

struct SrcList_item *pItem = pSrc->a;

Table *pTab;

assert( pItem && pSrc->nSrc==1 );

pTab = sqlite3LocateTableItem(pParse, 0, pItem);

sqlite3DeleteTable(pParse->db, pItem->pTab);

pItem->pTab = pTab;

if( pTab ){

pTab->nRef++;

}

if( sqlite3IndexedByLookup(pParse, pItem) ){

pTab = 0;

}

return pTab;

}

** Check to make sure the given table is writable. If it is not

** writable, generate an error message and return 1. If it is

** writable return 0;

int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){

/* A table is not writable under the following circumstances:

** 1) It is a virtual table and no implementation of the xUpdate method

** has been provided, or

** 2) It is a system table (i.e. sqlite_master), this call is not

** part of a nested parse and writable_schema pragma has not

** been specified.

** In either case leave an error message in pParse and return non-zero.

if( ( IsVirtual(pTab)

&& sqlite3GetVTable(pParse->db, pTab)->pMod->pModule->xUpdate==0 )

|| ( (pTab->tabFlags & TF_Readonly)!=0

&& (pParse->db->flags & SQLITE_WriteSchema)==0

&& pParse->nested==0 )

){

sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);

return 1;

}

#ifndef SQLITE_OMIT_VIEW

if( !viewOk && pTab->pSelect ){

sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);

return 1;

}

#endif

return 0;

}

#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)

** Evaluate a view and store its result in an ephemeral table. The

** pWhere argument is an optional WHERE clause that restricts the

** set of rows in the view that are to be added to the ephemeral table.

void sqlite3MaterializeView(

Parse *pParse, /* Parsing context */

Table *pView, /* View definition */

Expr *pWhere, /* Optional WHERE clause to be added */

int iCur /* Cursor number for ephemerial table */

){

SelectDest dest;

Select *pSel;

SrcList *pFrom;

sqlite3 *db = pParse->db;

int iDb = sqlite3SchemaToIndex(db, pView->pSchema);

pWhere = sqlite3ExprDup(db, pWhere, 0);

pFrom = sqlite3SrcListAppend(db, 0, 0, 0);

if( pFrom ){

assert( pFrom->nSrc==1 );

pFrom->a[0].zName = sqlite3DbStrDup(db, pView->zName);

pFrom->a[0].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zName);

assert( pFrom->a[0].pOn==0 );

assert( pFrom->a[0].pUsing==0 );

}

pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);

if( pSel ) pSel->selFlags |= SF_Materialize;

sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);

sqlite3Select(pParse, pSel, &dest);

sqlite3SelectDelete(db, pSel);

}

#endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */

#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)

** Generate an expression tree to implement the WHERE, ORDER BY,

** and LIMIT/OFFSET portion of DELETE and UPDATE statements.

** DELETE FROM table_wxyz WHERE a<5 ORDER BY a LIMIT 1;

** \__________________________/

** pLimitWhere (pInClause)

Expr *sqlite3LimitWhere(

Parse *pParse, /* The parser context */

SrcList *pSrc, /* the FROM clause -- which tables to scan */

Expr *pWhere, /* The WHERE clause. May be null */

ExprList *pOrderBy, /* The ORDER BY clause. May be null */

Expr *pLimit, /* The LIMIT clause. May be null */

Expr *pOffset, /* The OFFSET clause. May be null */

char *zStmtType /* Either DELETE or UPDATE. For error messages. */

){

Expr *pWhereRowid = NULL; /* WHERE rowid .. */

Expr *pInClause = NULL; /* WHERE rowid IN ( select ) */

Expr *pSelectRowid = NULL; /* SELECT rowid ... */

ExprList *pEList = NULL; /* Expression list contaning only pSelectRowid */

SrcList *pSelectSrc = NULL; /* SELECT rowid FROM x ... (dup of pSrc) */

Select *pSelect = NULL; /* Complete SELECT tree */

/* Check that there isn't an ORDER BY without a LIMIT clause.

if( pOrderBy && (pLimit == 0) ) {

sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);

goto limit_where_cleanup_2;

}

/* We only need to generate a select expression if there

** is a limit/offset term to enforce.

if( pLimit == 0 ) {

/* if pLimit is null, pOffset will always be null as well. */

assert( pOffset == 0 );

return pWhere;

}

/* Generate a select expression tree to enforce the limit/offset

** term for the DELETE or UPDATE statement. For example:

** DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1

** becomes:

** DELETE FROM table_a WHERE rowid IN (

** SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1

** );

pSelectRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);

if( pSelectRowid == 0 ) goto limit_where_cleanup_2;

pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid);

if( pEList == 0 ) goto limit_where_cleanup_2;

/* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree

** and the SELECT subtree. */

pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc, 0);

if( pSelectSrc == 0 ) {

sqlite3ExprListDelete(pParse->db, pEList);

goto limit_where_cleanup_2;

}

/* generate the SELECT expression tree. */

pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,

pOrderBy,0,pLimit,pOffset);

if( pSelect == 0 ) return 0;

/* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */

pWhereRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);

if( pWhereRowid == 0 ) goto limit_where_cleanup_1;

pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);

if( pInClause == 0 ) goto limit_where_cleanup_1;

pInClause->x.pSelect = pSelect;

pInClause->flags |= EP_xIsSelect;

sqlite3ExprSetHeight(pParse, pInClause);

return pInClause;

/* something went wrong. clean up anything allocated. */

limit_where_cleanup_1:

sqlite3SelectDelete(pParse->db, pSelect);

return 0;

limit_where_cleanup_2:

sqlite3ExprDelete(pParse->db, pWhere);

sqlite3ExprListDelete(pParse->db, pOrderBy);

sqlite3ExprDelete(pParse->db, pLimit);

sqlite3ExprDelete(pParse->db, pOffset);

return 0;

}

#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */

** Generate code for a DELETE FROM statement.

** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;

** \________/ \________________/

** pTabList pWhere

void sqlite3DeleteFrom(

Parse *pParse, /* The parser context */

SrcList *pTabList, /* The table from which we should delete things */

Expr *pWhere /* The WHERE clause. May be null */

){

Vdbe *v; /* The virtual database engine */

Table *pTab; /* The table from which records will be deleted */

const char *zDb; /* Name of database holding pTab */

int end, addr = 0; /* A couple addresses of generated code */

int i; /* Loop counter */

WhereInfo *pWInfo; /* Information about the WHERE clause */

Index *pIdx; /* For looping over indices of the table */

int iCur; /* VDBE Cursor number for pTab */

sqlite3 *db; /* Main database structure */

AuthContext sContext; /* Authorization context */

NameContext sNC; /* Name context to resolve expressions in */

int iDb; /* Database number */

int memCnt = -1; /* Memory cell used for change counting */

int rcauth; /* Value returned by authorization callback */

#ifndef SQLITE_OMIT_TRIGGER

int isView; /* True if attempting to delete from a view */

Trigger *pTrigger; /* List of table triggers, if required */

#endif

memset(&sContext, 0, sizeof(sContext));

db = pParse->db;

if( pParse->nErr || db->mallocFailed ){

goto delete_from_cleanup;

}

assert( pTabList->nSrc==1 );

/* Locate the table which we want to delete. This table has to be

** put in an SrcList structure because some of the subroutines we

** will be calling are designed to work with multiple tables and expect

** an SrcList* parameter instead of just a Table* parameter.

pTab = sqlite3SrcListLookup(pParse, pTabList);

if( pTab==0 ) goto delete_from_cleanup;

/* Figure out if we have any triggers and if the table being

** deleted from is a view

#ifndef SQLITE_OMIT_TRIGGER

pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);

isView = pTab->pSelect!=0;

#else

# define pTrigger 0

# define isView 0

#endif

#ifdef SQLITE_OMIT_VIEW

# undef isView

# define isView 0

#endif

/* If pTab is really a view, make sure it has been initialized.

if( sqlite3ViewGetColumnNames(pParse, pTab) ){

goto delete_from_cleanup;

}

if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){

goto delete_from_cleanup;

}

iDb = sqlite3SchemaToIndex(db, pTab->pSchema);

assert( iDb<db->nDb );

zDb = db->aDb[iDb].zName;

rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);

assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );

if( rcauth==SQLITE_DENY ){

goto delete_from_cleanup;

}

assert(!isView || pTrigger);

/* Assign cursor number to the table and all its indices.

assert( pTabList->nSrc==1 );

iCur = pTabList->a[0].iCursor = pParse->nTab++;

for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){

pParse->nTab++;

}

/* Start the view context

if( isView ){

sqlite3AuthContextPush(pParse, &sContext, pTab->zName);

}

/* Begin generating code.

v = sqlite3GetVdbe(pParse);

if( v==0 ){

goto delete_from_cleanup;

}

if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);

sqlite3BeginWriteOperation(pParse, 1, iDb);

/* If we are trying to delete from a view, realize that view into

** a ephemeral table.

#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)

if( isView ){

sqlite3MaterializeView(pParse, pTab, pWhere, iCur);

}

#endif

/* Resolve the column names in the WHERE clause.

memset(&sNC, 0, sizeof(sNC));

sNC.pParse = pParse;

sNC.pSrcList = pTabList;

if( sqlite3ResolveExprNames(&sNC, pWhere) ){

goto delete_from_cleanup;

}

/* Initialize the counter of the number of rows deleted, if

** we are counting rows.

if( db->flags & SQLITE_CountRows ){

memCnt = ++pParse->nMem;

sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);

}

#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION

/* Special case: A DELETE without a WHERE clause deletes everything.

** It is easier just to erase the whole table. Prior to version 3.6.5,

** this optimization caused the row change count (the value returned by

** API function sqlite3_count_changes) to be set incorrectly. */

if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab)

&& 0==sqlite3FkRequired(pParse, pTab, 0, 0)

){

assert( !isView );

sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,

pTab->zName, P4_STATIC);

for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){

assert( pIdx->pSchema==pTab->pSchema );

sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);

}

}else

#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */

/* The usual case: There is a WHERE clause so we have to scan through

** the table and pick which records to delete.

{

int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */

int iRowid = ++pParse->nMem; /* Used for storing rowid values. */

int regRowid; /* Actual register containing rowids */

/* Collect rowids of every row to be deleted.

sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);

pWInfo = sqlite3WhereBegin(

pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK, 0

);

if( pWInfo==0 ) goto delete_from_cleanup;

regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);

sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);

if( db->flags & SQLITE_CountRows ){

sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);

}

sqlite3WhereEnd(pWInfo);

/* Delete every item whose key was written to the list during the

** database scan. We have to delete items after the scan is complete

** because deleting an item can change the scan order. */

end = sqlite3VdbeMakeLabel(v);

/* Unless this is a view, open cursors for the table we are

** deleting from and all its indices. If this is a view, then the

** only effect this statement has is to fire the INSTEAD OF

** triggers. */

if( !isView ){

sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);

}

addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);

/* Delete the row */

#ifndef SQLITE_OMIT_VIRTUALTABLE

if( IsVirtual(pTab) ){

const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);

sqlite3VtabMakeWritable(pParse, pTab);

sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);

sqlite3VdbeChangeP5(v, OE_Abort);

sqlite3MayAbort(pParse);

}else

#endif

{

int count = (pParse->nested==0); /* True to count changes */

sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);

}

/* End of the delete loop */

sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);

sqlite3VdbeResolveLabel(v, end);

/* Close the cursors open on the table and its indexes. */

if( !isView && !IsVirtual(pTab) ){

for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){

sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);

}

sqlite3VdbeAddOp1(v, OP_Close, iCur);

}

/* Update the sqlite_sequence table by storing the content of the

** maximum rowid counter values recorded while inserting into

** autoincrement tables.

if( pParse->nested==0 && pParse->pTriggerTab==0 ){

sqlite3AutoincrementEnd(pParse);

}

/* Return the number of rows that were deleted. If this routine is

** generating code because of a call to sqlite3NestedParse(), do not

** invoke the callback function.

if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){

sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);

sqlite3VdbeSetNumCols(v, 1);

sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);

}

delete_from_cleanup:

sqlite3AuthContextPop(&sContext);

sqlite3SrcListDelete(db, pTabList);

sqlite3ExprDelete(db, pWhere);

return;

}

/* Make sure "isView" and other macros defined above are undefined. Otherwise

** thely may interfere with compilation of other functions in this file

** (or in another file, if this file becomes part of the amalgamation). */

#ifdef isView

#undef isView

#endif

#ifdef pTrigger

#undef pTrigger

#endif

** This routine generates VDBE code that causes a single row of a

** single table to be deleted.

** The VDBE must be in a particular state when this routine is called.

** These are the requirements:

** 1. A read/write cursor pointing to pTab, the table containing the row

** to be deleted, must be opened as cursor number $iCur.

** 2. Read/write cursors for all indices of pTab must be open as

** cursor number base+i for the i-th index.

** 3. The record number of the row to be deleted must be stored in

** memory cell iRowid.

** This routine generates code to remove both the table record and all

** index entries that point to that record.

void sqlite3GenerateRowDelete(

Parse *pParse, /* Parsing context */

Table *pTab, /* Table containing the row to be deleted */

int iCur, /* Cursor number for the table */

int iRowid, /* Memory cell that contains the rowid to delete */

int count, /* If non-zero, increment the row change counter */

Trigger *pTrigger, /* List of triggers to (potentially) fire */

int onconf /* Default ON CONFLICT policy for triggers */

){

Vdbe *v = pParse->pVdbe; /* Vdbe */

int iOld = 0; /* First register in OLD.* array */

int iLabel; /* Label resolved to end of generated code */

/* Vdbe is guaranteed to have been allocated by this stage. */

assert( v );

/* Seek cursor iCur to the row to delete. If this row no longer exists

** (this can happen if a trigger program has already deleted it), do

** not attempt to delete it or fire any DELETE triggers. */

iLabel = sqlite3VdbeMakeLabel(v);

sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);

/* If there are any triggers to fire, allocate a range of registers to

** use for the old.* references in the triggers. */

if( sqlite3FkRequired(pParse, pTab, 0, 0) || pTrigger ){

u32 mask; /* Mask of OLD.* columns in use */

int iCol; /* Iterator used while populating OLD.* */

/* TODO: Could use temporary registers here. Also could attempt to

** avoid copying the contents of the rowid register. */

mask = sqlite3TriggerColmask(

pParse, pTrigger, 0, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onconf

);

mask |= sqlite3FkOldmask(pParse, pTab);

iOld = pParse->nMem+1;

pParse->nMem += (1 + pTab->nCol);

/* Populate the OLD.* pseudo-table register array. These values will be

** used by any BEFORE and AFTER triggers that exist. */

sqlite3VdbeAddOp2(v, OP_Copy, iRowid, iOld);

for(iCol=0; iCol<pTab->nCol; iCol++){

if( mask==0xffffffff || mask&(1<<iCol) ){

sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, iCol, iOld+iCol+1);

}

/* Invoke BEFORE DELETE trigger programs. */

sqlite3CodeRowTrigger(pParse, pTrigger,

TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel

);

/* Seek the cursor to the row to be deleted again. It may be that

** the BEFORE triggers coded above have already removed the row

** being deleted. Do not attempt to delete the row a second time, and

** do not fire AFTER triggers. */

sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);

/* Do FK processing. This call checks that any FK constraints that

** refer to this table (i.e. constraints attached to other tables)

** are not violated by deleting this row. */

sqlite3FkCheck(pParse, pTab, iOld, 0);

}

/* Delete the index and table entries. Skip this step if pTab is really

** a view (in which case the only effect of the DELETE statement is to

** fire the INSTEAD OF triggers). */

if( pTab->pSelect==0 ){

sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);

sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));

if( count ){

sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);

}

/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to

** handle rows (possibly in other tables) that refer via a foreign key

** to the row just deleted. */

sqlite3FkActions(pParse, pTab, 0, iOld);

/* Invoke AFTER DELETE trigger programs. */

sqlite3CodeRowTrigger(pParse, pTrigger,

TK_DELETE, 0, TRIGGER_AFTER, pTab, iOld, onconf, iLabel

);

/* Jump here if the row had already been deleted before any BEFORE

** trigger programs were invoked. Or if a trigger program throws a

** RAISE(IGNORE) exception. */

sqlite3VdbeResolveLabel(v, iLabel);

}

** This routine generates VDBE code that causes the deletion of all

** index entries associated with a single row of a single table.

** The VDBE must be in a particular state when this routine is called.

** These are the requirements:

** 1. A read/write cursor pointing to pTab, the table containing the row

** to be deleted, must be opened as cursor number "iCur".

** 2. Read/write cursors for all indices of pTab must be open as

** cursor number iCur+i for the i-th index.

** 3. The "iCur" cursor must be pointing to the row that is to be

** deleted.

void sqlite3GenerateRowIndexDelete(

Parse *pParse, /* Parsing and code generating context */

Table *pTab, /* Table containing the row to be deleted */

int iCur, /* Cursor number for the table */

int *aRegIdx /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */

){

int i;

Index *pIdx;

int r1;

for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){

if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;

r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);

sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);

}

** Generate code that will assemble an index key and put it in register

** regOut. The key with be for index pIdx which is an index on pTab.

** iCur is the index of a cursor open on the pTab table and pointing to

** the entry that needs indexing.

** Return a register number which is the first in a block of

** registers that holds the elements of the index key. The

** block of registers has already been deallocated by the time

** this routine returns.

int sqlite3GenerateIndexKey(

Parse *pParse, /* Parsing context */

Index *pIdx, /* The index for which to generate a key */

int iCur, /* Cursor number for the pIdx->pTable table */

int regOut, /* Write the new index key to this register */

int doMakeRec /* Run the OP_MakeRecord instruction if true */

){

Vdbe *v = pParse->pVdbe;

int j;

Table *pTab = pIdx->pTable;

int regBase;

int nCol;

nCol = pIdx->nColumn;

regBase = sqlite3GetTempRange(pParse, nCol+1);

sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);

for(j=0; j<nCol; j++){

int idx = pIdx->aiColumn[j];

if( idx==pTab->iPKey ){

sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);

}else{

sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);

sqlite3ColumnDefault(v, pTab, idx, -1);

}

if( doMakeRec ){

const char *zAff;

if( pTab->pSelect

|| OptimizationDisabled(pParse->db, SQLITE_IdxRealAsInt)

){

zAff = 0;

}else{

zAff = sqlite3IndexAffinityStr(v, pIdx);

}

sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);

sqlite3VdbeChangeP4(v, -1, zAff, P4_TRANSIENT);

}

sqlite3ReleaseTempRange(pParse, regBase, nCol+1);

return regBase;

}

sqlcipher/src/delete.c at multi-lib · securitykernel/sqlcipher · GitHub

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